Furniture hinge

ABSTRACT

A furniture hinge has a hinge arm connectible to the body of a piece of furniture and a lever connectible to a closure for the furniture. The closure is movable between a closed position and an open position. A damping device is disposed between the hinge arm and the lever and includes a housing having a bellows-like first part and a second part secured to the hinge arm. A piston rides in the housing and divides it into first and second chambers. The piston is provided with flow channels which allow hydraulic fluid in the housing to flow between the first and second chambers. The piston is mounted on a rod which extends through, and is coupled to, the first housing part and is articulately connected to the lever. A sealing member likewise mounted on the rod is arranged to seal the flow channels upon movement of the closure to its closed position. As the closure moves to its open position, the rod moves out of the housing with an accompanying expansion of the first housing part and unblocking of the flow channels. The pressure in the first chamber is reduced so that the fluid enters this chamber via the flow channels. Upon movement of the closure to its closed position, the rod moves into the housing and the flow channels are sealed. Fluid then flows from the first chamber to the second chamber by leakage. This may be accomplished by providing the sealing member with a slit and making the second housing part or the sealing member elastically deformable. Alternatively, the piston may be formed with an elastically deformable sealing lip which engages the inner surface of the housing.

BACKGROUND OF THE INVENTION

The invention relates to a furniture hinge having hinge components whichcan be affixed to the body of the furniture and to a door or cover andalso having at least one lever which is articulately connected withthese hinge components.

Most furniture hinges of this type are equipped with a spring mechanismwhich automatically closes the door, the cover or the like. The closingmotion due to the spring force frequently leads to disturbing slammingsounds.

In many cases, externally acting forces, e.g., resulting from manualmanipulation of the door panel, are superimposed on the closing forcedue to the spring mechanism. This can intensify the closing sounds ofthe door or the like.

SUMMARY OF THE INVENTION

It is an object of the invention to design a furniture hinge of theabove type so that disturbing closing sounds are eliminated andexternally applied closing or opening forces are damped.

According to the invention, this object is achieved in that a dampingdevice provided with an incompressible hydraulic medium is arrangedbetween the lever and a hinge component and includes a piston rod whichis articulated to the lever, a piston secured to the piston rod and acylinder affixed to the hinge component and receiving the piston. Thecylinder is provided with an end cap which has a central through openingfor the piston rod and defines two chambers with the piston and thecylinder. Transfer openings or channels for the hydraulic medium areprovided in the region of the piston.

In the furniture hinge of the invention, the damping device is disposedbetween functional components of the furniture hinge without the need tochange the dimensions and/or the structure of the hinge components to beaffixed to the body of the furniture and to the door or cover.

Since furniture hinges are mass produced articles having limitedallowable cost, the damping device must likewise be economical tomanufacture and mount.

The damping device in accordance with the invention must be able towithstand the normal loading situation in which the door, the cover orthe like is closed by the relatively small force of the closing springof the furniture hinge as well as the exceptional situation in which thedoor or the like is activated by external influences such as manualpushing of the door to the closed position or manual opening of thedoor.

In an advantageous embodiment of the furniture hinge of the invention,the end cap anchored to the cylinder is constructed as an elasticallydeformable bellows having a through channel for the piston rod, and theend cap is fixed to the piston rod in a fluidtight fashion in the regionof this through channel. The through channel can have an inwardlyprojecting annular bead which extends into an annular groove of thepiston rod.

Due to the elasticity of the bellows-shaped end cap and the inwardlyprojecting annular bead, a lock with respect to both force and shape isdeveloped between the covering cap and the piston rod in the region ofthe through channel. As a result of this connection, sliding frictionbetween the piston rod and the covering cap is avoided during operationof the damping device. Furthermore, the covering cap is deformed in adirection towards the cylinder during the closing motion of the hinge.

Prior to initiation of the opening motion of the door or the furniturehinge, the damping fluid is to be found in the chamber bounded by thebellows-shaped end cap and the piston. If the opening motion isperformed very rapidly by hand, the covering cap is elastically deformedso that the piston rod can follow the rapid opening motion. Asubatmospheric pressure is then developed in the second cylinder chamberthereby causing a vapor bubble to form and forcing the hydraulic fluidto flow out of the first chamber into the second at increased speed sothat the elastic deformation of the covering cap is reversed and theopening motion can be carried out virtually undamped.

If, during the closing motion of the hinge which is checked by thedamping device, a load peak arises, the flow cross section between thetwo chambers of the damping device can be increased by elasticdeformation of the cylinder and/or the piston. After disappearance ofthe load peak, this increase in the flow cross section is reversed.

BRIEF DESCRIPTION OF THE DRAWINGS

Additional features of the invention are set forth in the followingdescription of advantageous exemplary embodiments illustrated in thedrawings where:

FIG. 1 shows a furniture hinge which is equipped with a damping deviceand is in the closed position,

FIG. 2 shows the furniture hinge of FIG. 1 in the open position,

FIG. 3 is a sectional perspective view of one embodiment of the dampingdevice,

FIG. 4 is a view in the direction of the arrow IV in FIG. 3,

FIG. 5 shows the damping device of FIG. 3 during the opening motion,

FIG. 6 is a vertical section through the damping device of FIGS. 3 to 5showing the closed position of the furniture hinge on the left and theopen position on the right,

FIG. 7 is a fragmentary view of another embodiment of the dampingdevice, and

FIG. 8 is a sectional perspective view of a further embodiment of thedamping device.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

The furniture hinge of FIGS. 1 and 2 has a pot-like housing 4 which isarranged and fixed in a recess 2 of a furniture door 3 and isarticulately connected via levers 5 and 6 to a hinge arm 7 secured tothe body of the furniture.

The lever 6 is constructed as a two-armed lever and has a lever arm 8which is articulately connected to a piston rod 9 of a damping device10. This piston rod extends into a housing of the damping device whichas best seen in FIG. 6, is defined by a bellows-shaped covering cap 11of elastic material, a cylinder 12 and a pot-shaped cap 13 which isdisposed on the cylinder in an inverted position.

The cylinder is equipped with an annular flange 14 and projects througha bore 15 (see FIG. 6) in a wall 16 of the hinge arm 7. The annularflange 14 lies against the inner side of the wall 16 of the hinge arm 7while the cap 13 extends to the vicinity of the hinge arm.

FIGS. 1 and 2 show that the damping device 10 is integrated in thestructure of the furniture hinge and requires no significant redesign ofthe functional components of this hinge.

As shown in FIG. 6, the cylinder 12 includes a cylindrical portion 17which extends from the annular flange 14, is open-ended and, at itsouter periphery, is equipped with anchoring ribs 18,19 to which afastening flange 20 of the covering cap 11 is affixed.

The covering cap is equipped with an inwardly extending stub 21 whichdefines a through channel for the piston rod 9.

The central region of the stub 21 is provided with an inwardlyprojecting annular bead 22 which engages in an annular groove 23 of thepiston rod 9.

FIG. 6 shows that the outer end of the stub 21 lies against a shoulder24 of the piston rod 9.

The covering cap 11 is constructed in a bellows-like fashion between thefastening flange 20 and the stub 21. It is made of an elasticallydeformable material, e.g., rubber or a rubber-like plastic. It candeform elastically in response to increased pressure from the dampingfluid and, due to its flexibility, can follow the movement of the pistonrod between the closed and open positions of the furniture hinge.

In the embodiment of the damping device 10 according to FIGS. 3 to 6, apiston 25 is provided at the free end of the piston rod 9, bears againsta shoulder surface 26 of the piston rod and is fixed by a retaining ring27 which can be snapped onto the piston rod. An arresting edge 28 of theretaining ring 27 engages behind an abutment surface 29 of the pistonrod.

The outer diameter of the piston 25, as well as that of the retainingring 27, is smaller than the inner diameter of the cylinder 12.

Flow channels 30,31 are arranged in the piston 25 and the retaining ring27.

The piston 25 and the retaining ring 27 define a receiving groove 32 fora piston ring 33 which is axially movable in this receiving groove.

The side of the piston ring 33 facing the retaining ring 27 is equippedwith a distancing cam 34 which bears against the underside of theretaining ring 27 during the opening stroke of the piston andestablishes a flow connection between the chamber 35 and the chamber 36of the cylinder. In this operating position, the piston ring 33 freesthe flow channel or flow channels 30 in the piston.

The side of the piston ring facing the piston has a cam 37 which engagesin a flow channel 30 of the piston 25 and constitutes a means forpreventing rotation of the piston ring relative to the piston.

The outer diameter of the piston ring 33 corresponds to the innerdiameter of the cylinder 12.

The piston ring is equipped with a slit 38 which extends across theentire width of the ring. FIG. 4 shows that the retaining ring 27 has noflow channel 31, and the piston 25 has no flow channel 30, in the regionof the slit 38. Even when the slit 38 is largely covered by theretaining ring 27 or by the piston 25, a portion of the slit, which isidentified by the reference numeral 39 in FIG. 4, remains as a flowcross section.

In order to ensure that the flow opening 39 of the slit 38 remainsunobstructed, i.e., is not accidentally distorted in any operating phaseby lateral play of the piston 25, the periphery of the piston 25 can beprovided with guiding cams, recesses and/or flattened areas which arearranged so as to create a free space between the peripheral surface ofthe piston and the wall of the cylinder at least in the region of theflow opening 39.

FIGS. 3 and 6 show that the flow channels 30 are closed by the pistonring 33 during movement of the piston to the closed position (orterminal position) so that the portion 39 of the piston ring 33 remainsas the sole flow cross section.

If the pressure of the damping fluid in the chamber 36 is increased byforces applied to the door from externally, the flow cross section canbe enlarged in that the cylinder 12 is made of an elastically deformablematerial and thus deforms elastically during this load peak so that thecylinder wall moves away from the piston ring 33 and an additional flowcross section is created.

If the piston is moved from the closed position to the open positionillustrated in FIG. 5, the piston ring 33 in the receiving groove 32assumes an intermediate position determined by the distancing cam 34 sothat the damping fluid can flow from the chamber 35 to the chamber 36through the flow channels 30 and 31.

When the cylinder 12 is made of a non-elastic material as in theembodiment of FIG. 7, load peaks arising during the closing stroke ofthe piston can be counteracted by providing the side of the piston ring33a which faces the chamber 36 with an inclined surface 40. During aload peak, the latter is subjected to an increased pressure from thechamber 36 so that the piston ring is compressed in the region of theslit 38 and an additional flow cross section is thereby generatedbetween the piston ring and the inner wall of the cylinder.

Another exemplary embodiment of the damping device 10 is illustrated inFIG. 8.

In this construction, the piston 41 is equipped with flow channels 42and is slidably mounted at the free end of the piston rod 9 between aretaining ring 43 fixed to the end of the piston rod and a cover plate44 for the flow channels 42.

During the opening stroke of the piston 41, the latter lies against theretaining ring 43 so that the damping fluid can flow out of the chamber35 into the chamber 36 through the channels 42.

During the closing stroke of the piston, the piston assumes theoperating position shown in FIG. 8. The flow channels 42 are closed bythe cover plate 44 so that the damping fluid can flow out of the chamber36 into the chamber 35 only when the circumferentially complete sealinglip 45 lying against the inner wall of the cylinder is elasticallydeformed inwards by the fluid pressure in the chamber 36 therebycreating a free cross section between the sealing lip and the inner wallof the cylinder.

In this embodiment, the piston 41 must thus consist of an elasticallydeformable material. It is preferably made of rubber or a rubber-likeplastic.

We claim:
 1. A hinge for an item of furniture having a main structureand a closure for the main structure, comprising a first hinge componentmountable on the main structure; a second hinge component mountable onthe closure; and a damping device located in one of said first andsecond hinge components connecting said first and second components,said damping device including a housing defining at least a portion ofthe exterior of said damping device having a compartment, a partition insaid compartment dividing the latter into first and second chambers, abody of hydraulic fluid in said compartment, and means for transferringsaid fluid between said chambers, said housing including an elasticallydeformable housing part.
 2. The hinge of claim 1, wherein said fluid issubstantially incompressible.
 3. The hinge of claim 1, wherein one ofsaid components comprises a lever designed for articulation.
 4. Thehinge of claim 3, wherein said damping device includes a rod having afirst end portion which is connected to said partition and a second endportion which is articulately connected to said lever, said housingbeing secured to the other of said components.
 5. The hinge of claim 1,wherein said partition includes a piston.
 6. The hinge of claim 1,wherein said housing includes a cylinder having an open end, and a coverfor said open end.
 7. The hinge of claim 6, wherein said damping deviceincludes a rod having a first end portion which is connected to saidpartition and a second end portion which is connected to one of saidcomponents, said cover being provided with a substantially centrallylocated passage, and said rod extending through said passage.
 8. Thehinge of claim 6, wherein said cylinder has an end wall remote from saidcover, said end wall and said partition cooperating to define one ofsaid chambers, and said cover and said partition cooperating to definethe other of said chambers.
 9. The hinge of claim 1, wherein saidtransferring means comprises flow channels in the region of saidpartition.
 10. The hinge of claim 1, wherein said housing part isbellows-like.
 11. The hinge of claim 1, wherein said damping deviceincludes a rod having a first end portion which is connected to saidpartition and a second end portion which is connected to one of saidcomponents, said housing part being provided with a passage, and saidrod extending through, and being fixed to said housing part in asubstantially fluidtight manner in the region of said passage.
 12. Thehinge of claim 11, wherein said rod is provided with a groove, saidhousing part including a tubular portion defining said passage, and saidtubular portion having a projection which is received in said groove.13. The hinge of claim 12, wherein said groove and said projection aresubstantially annular.
 14. The hinge of claim 12, wherein said tubularportion has a central region and said projection is disposed in saidcentral region.
 15. The hinge of claim 12, wherein said rod has ashoulder and said tubular portion has an end portion facing outward ofsaid housing, said end portion bearing against said shoulder.
 16. Thehinge of claim 1, wherein said housing part comprises rubber or arubber-like plastic.
 17. The hinge of claim 1, wherein said housing hasa flange, a tubular section extending from said flange and having anopen end, and a cover for said open end, said tubular section and saidcover being provided with cooperating rib-like elements for securingsaid cover to said tubular section.
 18. The hinge of claim 17, whereinsaid flange is substantially annular.
 19. A hinge for an item offurniture having a main structure and a closure for the main structure,comprising a first hinge component mountable on the main structure; asecond hinge component mountable on the closure; and a damping devicelocated in one of said first and second hinge components connecting saidfirst and second components, said damping device including a housingdefining at least a portion of the exterior of said damping devicehaving a compartment, a partition in said compartment dividing thelatter into first and second chambers, a body of hydraulic fluid in saidcompartment, and means for transferring said fluid between saidchambers, said housing having a flange, a tubular section extending fromsaid flange and having an open end, and a cover for said open end, saidtubular section and said cover being provided with cooperating rib-likeelements for securing said cover to said tubular section, one of saidcomponents including a wall having oppositely facing first and secondsurfaces, and said wall being provided with a bore which extends betweensaid surfaces, said flange bearing against said first surface, and saidhousing having another section which is located on the side of saidflange remote from said tubular section and projects through said bore,said damping device further comprising a retaining element which atleast partially surrounds said other section.
 20. The hinge of claim 19,wherein said one component is said first component.
 21. The hinge ofclaim 19, wherein said one component comprises a hinge arm whichincludes said wall.
 22. The hinge of claim 19, wherein said onecomponent has a hollow interior and said first surface is located insaid hollow interior.
 23. The hinge of claim 19, wherein said retainingelement comprises a cap having a skirt which terminates proximate tosaid flange.
 24. A hinge for an item of furniture having a mainstructure and a closure for the main structure, comprising a first hingecomponent mountable on the main structure; a second hinge componentmountable on the closure; and a damping device located in one of saidfirst and second hinge components connecting said first and secondcomponents, said damping device including a housing defining at least aportion of the exterior of said damping device having a compartment, apartition in said compartment dividing the latter into first and secondchambers, a body of hydraulic fluid in said compartment, and means fortransferring said fluid between said chambers, said housing including acylinder which is elastically deformable in response to pressure exertedby said fluid.
 25. A hinge for an item of furniture having a mainstructure and a closure for the main structure, comprising a first hingecomponent mountable on the main structure; a second hinge componentmountable on the closure; and a damping device located in one of saidfirst and second hinge components connecting said first and secondcomponents, said damping device including a housing defining at least aportion of the exterior of said damping device having a compartment, apartition in said compartment dividing the latter into first and secondchambers, a body of hydraulic fluid in said compartment, means fortransferring said fluid between said chambers, and a rod having a firstend portion which is connected to said partition and a second endportion which is connected to one of said components, said partitioncomprising a piston, a retaining ring defining a space with said piston,and a piston ring in said space movable axially of said rod, saidtransferring means including a slit in said piston ring.
 26. The hingeof claim 25, wherein said transferring means further includes at leastone flow channel in said piston and at least one flow channel in saidretaining ring.
 27. The hinge of claim 26, wherein said piston ring isarranged to close said flow channel of said piston upon movement of saidcomponents to a closed position.
 28. The hinge of claim 25, wherein saidcompartment has a predetermined diameter and said piston ring has adiameter substantially equal to said predetermined diameter, said pistonand said retaining ring having diameters smaller than said predetermineddiameter.
 29. The hinge of claim 25, wherein said transferring meansfurther includes at least one flow channel in said piston, said pistonring being provided with a protuberance receivable in said flow channel.30. The hinge of claim 25, wherein said piston ring is provided with atleast one protuberance which faces said retaining ring and is arrangedto bear against the same upon movement of said components to an openposition.
 31. The hinge of claim 25, wherein said piston ring has asurface portion which is inclined with respect to the axis of said rodand faces one of said chambers.
 32. The hinge of claim 31, wherein saidsurface portion is substantially unbroken.
 33. The hinge of claim 31,wherein said piston ring has an edge portion and said surface portion isprovided on said marginal portion.
 34. The hinge of claim 31, whereinsaid transferring means further includes at least one flow channel insaid piston and said piston ring is arranged to close said flow channelupon movement of said components to a closed position, said fluidflowing from said one chamber to the other of said chambers duringmovement of said components to said closed position.
 35. A hinge for anitem of furniture having a main structure and a closure for the mainstructure, comprising a first hinge component mountable on the mainstructure; a second hinge component mountable on the closure; and adamping device located in one of said first and second hinge componentsconnecting said first and second components, said damping deviceincluding a housing defining at least a portion of the exterior of saiddamping device having a compartment, a partition in said compartmentdividing the latter into first and second chambers, a body of hydraulicfluid in said compartment, means for transferring said fluid betweensaid chambers, and a rod having a first end portion which is connectedto said partition and a second end portion which is connected to one ofsaid components, said partition comprising a retaining member, a coverplate spaced from said retaining member, and a piston movable axially ofsaid rod between said retaining member and said cover plate, said pistonbeing provided with a sealing lip.
 36. The hinge of claim 35, whereinsaid fluid flows from one of said chambers to the other of said chambersduring movement of said components to a closed position and said sealinglip is inclined from said one chamber to said other chamber asconsidered in a direction radially outward of said rod.
 37. The hinge ofclaim 35, wherein said transferring means includes at least one flowchannel in said piston extending axially of said rod, said piston beingarranged to move into engagement with said cover plate upon movement ofsaid components to a closed position so that said cover plate closessaid flow channel.
 38. The hinge of claim 35, wherein said sealing lipis substantially unbroken.